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<a href="#pub-types">Public Types</a> &#124;
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<p><a class="el" href="class_qwt_color_map.html" title="QwtColorMap is used to map values into colors. ">QwtColorMap</a> is used to map values into colors.  
 <a href="class_qwt_color_map.html#details">More...</a></p>

<p><code>#include &lt;<a class="el" href="qwt__color__map_8h_source.html">qwt_color_map.h</a>&gt;</code></p>
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Inheritance diagram for QwtColorMap:</div>
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<area shape="rect" id="node2" href="class_qwt_alpha_color_map.html" title="QwtAlphaColorMap varies the alpha value of a color. " alt="" coords="5,80,144,107"/>
<area shape="rect" id="node3" href="class_qwt_linear_color_map.html" title="QwtLinearColorMap builds a color map from color stops. " alt="" coords="168,80,309,107"/>
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<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="pub-types"></a>
Public Types</h2></td></tr>
<tr class="memitem:a9e5570790910fa3894887bca7dc5a670"><td class="memItemLeft" align="right" valign="top">enum &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670">Format</a> { <a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670a663473fd836d9a84fe48ae1755de326a">RGB</a>, 
<a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670a304cb055c004223ca77f1a4cbbf27ea2">Indexed</a>
 }</td></tr>
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<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="pub-methods"></a>
Public Member Functions</h2></td></tr>
<tr class="memitem:a2ab0a6041ea6d37c0609ca2e3bd976ca"><td class="memItemLeft" align="right" valign="top"><a id="a2ab0a6041ea6d37c0609ca2e3bd976ca"></a>
&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#a2ab0a6041ea6d37c0609ca2e3bd976ca">QwtColorMap</a> (<a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670">Format</a>=<a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670a663473fd836d9a84fe48ae1755de326a">QwtColorMap::RGB</a>)</td></tr>
<tr class="memdesc:a2ab0a6041ea6d37c0609ca2e3bd976ca"><td class="mdescLeft">&#160;</td><td class="mdescRight">Constructor. <br /></td></tr>
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<tr class="memitem:af20e4ffdb3c5d34f5a6dc301bcbb9f7e"><td class="memItemLeft" align="right" valign="top"><a id="af20e4ffdb3c5d34f5a6dc301bcbb9f7e"></a>
virtual&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#af20e4ffdb3c5d34f5a6dc301bcbb9f7e">~QwtColorMap</a> ()</td></tr>
<tr class="memdesc:af20e4ffdb3c5d34f5a6dc301bcbb9f7e"><td class="mdescLeft">&#160;</td><td class="mdescRight">Destructor. <br /></td></tr>
<tr class="separator:af20e4ffdb3c5d34f5a6dc301bcbb9f7e"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a6a7defcce42e779c1596e277c78986c2"><td class="memItemLeft" align="right" valign="top"><a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670">Format</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#a6a7defcce42e779c1596e277c78986c2">format</a> () const</td></tr>
<tr class="separator:a6a7defcce42e779c1596e277c78986c2"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:aaed0bb47b6379696c588732348438136"><td class="memItemLeft" align="right" valign="top">virtual QRgb&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#aaed0bb47b6379696c588732348438136">rgb</a> (const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;interval, double value) const =0</td></tr>
<tr class="separator:aaed0bb47b6379696c588732348438136"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a762baa2edca8773ec09e0c1c5df2cf04"><td class="memItemLeft" align="right" valign="top">virtual unsigned char&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#a762baa2edca8773ec09e0c1c5df2cf04">colorIndex</a> (const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;interval, double value) const =0</td></tr>
<tr class="separator:a762baa2edca8773ec09e0c1c5df2cf04"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a7ef0ebd270a05712715bfdfbe59f35d5"><td class="memItemLeft" align="right" valign="top">QColor&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#a7ef0ebd270a05712715bfdfbe59f35d5">color</a> (const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;, double value) const</td></tr>
<tr class="separator:a7ef0ebd270a05712715bfdfbe59f35d5"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a2e41c503838aea8ed617958aa9b9e5bf"><td class="memItemLeft" align="right" valign="top">virtual QVector&lt; QRgb &gt;&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_color_map.html#a2e41c503838aea8ed617958aa9b9e5bf">colorTable</a> (const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;) const</td></tr>
<tr class="separator:a2e41c503838aea8ed617958aa9b9e5bf"><td class="memSeparator" colspan="2">&#160;</td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p><a class="el" href="class_qwt_color_map.html" title="QwtColorMap is used to map values into colors. ">QwtColorMap</a> is used to map values into colors. </p>
<p>For displaying 3D data on a 2D plane the 3rd dimension is often displayed using colors, like f.e in a spectrogram.</p>
<p>Each color map is optimized to return colors for only one of the following image formats:</p>
<ul>
<li>QImage::Format_Indexed8<br />
</li>
<li>QImage::Format_ARGB32<br />
 <dl class="section see"><dt>See also</dt><dd><a class="el" href="class_qwt_plot_spectrogram.html" title="A plot item, which displays a spectrogram. ">QwtPlotSpectrogram</a>, <a class="el" href="class_qwt_scale_widget.html" title="A Widget which contains a scale. ">QwtScaleWidget</a> </dd></dl>
</li>
</ul>
</div><h2 class="groupheader">Member Enumeration Documentation</h2>
<a id="a9e5570790910fa3894887bca7dc5a670"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a9e5570790910fa3894887bca7dc5a670">&#9670;&nbsp;</a></span>Format</h2>

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          <td class="memname">enum <a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670">QwtColorMap::Format</a></td>
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<p>Format for color mapping </p><dl class="section see"><dt>See also</dt><dd><a class="el" href="class_qwt_color_map.html#aaed0bb47b6379696c588732348438136">rgb()</a>, <a class="el" href="class_qwt_color_map.html#a762baa2edca8773ec09e0c1c5df2cf04">colorIndex()</a>, <a class="el" href="class_qwt_color_map.html#a2e41c503838aea8ed617958aa9b9e5bf">colorTable()</a> </dd></dl>
<table class="fieldtable">
<tr><th colspan="2">Enumerator</th></tr><tr><td class="fieldname"><a id="a9e5570790910fa3894887bca7dc5a670a663473fd836d9a84fe48ae1755de326a"></a>RGB&#160;</td><td class="fielddoc"><p>The map is intended to map into RGB values. </p>
</td></tr>
<tr><td class="fieldname"><a id="a9e5570790910fa3894887bca7dc5a670a304cb055c004223ca77f1a4cbbf27ea2"></a>Indexed&#160;</td><td class="fielddoc"><p>The map is intended to map into 8 bit values, that are indices into the color table. </p>
</td></tr>
</table>

</div>
</div>
<h2 class="groupheader">Member Function Documentation</h2>
<a id="a7ef0ebd270a05712715bfdfbe59f35d5"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a7ef0ebd270a05712715bfdfbe59f35d5">&#9670;&nbsp;</a></span>color()</h2>

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          <td class="memname">QColor QwtColorMap::color </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;&#160;</td>
          <td class="paramname"><em>interval</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>value</em>&#160;</td>
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          <td></td>
          <td>)</td>
          <td></td><td> const</td>
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<p>Map a value into a color</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">interval</td><td>Valid interval for values </td></tr>
    <tr><td class="paramname">value</td><td>Value</td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>Color corresponding to value</dd></dl>
<dl class="section warning"><dt>Warning</dt><dd>This method is slow for Indexed color maps. If it is necessary to map many values, its better to get the color table once and find the color using <a class="el" href="class_qwt_color_map.html#a762baa2edca8773ec09e0c1c5df2cf04">colorIndex()</a>. </dd></dl>

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<a id="a762baa2edca8773ec09e0c1c5df2cf04"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a762baa2edca8773ec09e0c1c5df2cf04">&#9670;&nbsp;</a></span>colorIndex()</h2>

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          <td class="memname">virtual unsigned char QwtColorMap::colorIndex </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;&#160;</td>
          <td class="paramname"><em>interval</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>value</em>&#160;</td>
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          <td>)</td>
          <td></td><td> const</td>
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<p>Map a value of a given interval into a color index</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">interval</td><td>Range for the values </td></tr>
    <tr><td class="paramname">value</td><td>Value </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>color index, corresponding to value </dd></dl>

<p>Implemented in <a class="el" href="class_qwt_linear_color_map.html#a0daffa17d380dd51b6186f75cf207ec6">QwtLinearColorMap</a>.</p>

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<a id="a2e41c503838aea8ed617958aa9b9e5bf"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a2e41c503838aea8ed617958aa9b9e5bf">&#9670;&nbsp;</a></span>colorTable()</h2>

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          <td class="memname">QVector&lt; QRgb &gt; QwtColorMap::colorTable </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;&#160;</td>
          <td class="paramname"><em>interval</em></td><td>)</td>
          <td> const</td>
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<p>Build and return a color map of 256 colors</p>
<p>The color table is needed for rendering indexed images in combination with using <a class="el" href="class_qwt_color_map.html#a762baa2edca8773ec09e0c1c5df2cf04">colorIndex()</a>.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">interval</td><td>Range for the values </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>A color table, that can be used for a QImage </dd></dl>

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<a id="a6a7defcce42e779c1596e277c78986c2"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a6a7defcce42e779c1596e277c78986c2">&#9670;&nbsp;</a></span>format()</h2>

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          <td class="memname"><a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670">QwtColorMap::Format</a> QwtColorMap::format </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td> const</td>
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<dl class="section return"><dt>Returns</dt><dd>Intended format of the color map </dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="class_qwt_color_map.html#a9e5570790910fa3894887bca7dc5a670">Format</a> </dd></dl>

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<a id="aaed0bb47b6379696c588732348438136"></a>
<h2 class="memtitle"><span class="permalink"><a href="#aaed0bb47b6379696c588732348438136">&#9670;&nbsp;</a></span>rgb()</h2>

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          <td class="memname">virtual QRgb QwtColorMap::rgb </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="class_qwt_interval.html">QwtInterval</a> &amp;&#160;</td>
          <td class="paramname"><em>interval</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>value</em>&#160;</td>
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          <td></td>
          <td>)</td>
          <td></td><td> const</td>
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<p>Map a value of a given interval into a RGB value.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">interval</td><td>Range for the values </td></tr>
    <tr><td class="paramname">value</td><td>Value </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>RGB value, corresponding to value </dd></dl>

<p>Implemented in <a class="el" href="class_qwt_alpha_color_map.html#a15815e2d6637941bc8e806afbb99c170">QwtAlphaColorMap</a>, and <a class="el" href="class_qwt_linear_color_map.html#a2b3a87791791eea4b53a94fafd541f9c">QwtLinearColorMap</a>.</p>

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